rsi: Add new firmware loading method

The older firmware loading method has been deprecated and not in use
for any chipets. New method is introduced which works based on soft
boot loader. In this method, complete RAM image and FLASH image are
present in the flash. Before loading the functional firmware, host
issues boot loader commands to verify whether firmware to load is
different from the current functional firmware. If not, firmware
upgrade progresses and boot loader will switch to the new functional
firmware.

"rs9113_wlan_qspi.rps" is the firmware filename used in this patch.

Signed-off-by: Prameela Rani Garnepudi <prameela.j04cs@gmail.com>
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>